Ask HN: Why is TypeScript language service so buggy?

I keep fighting the bugs in the intellisense and compilation. My local d.ts are sometimes not read, not matter what settings I use in tsconfig or where I put my d.ts. Sometimes external @types definitions are picked up, sometimes not. usually the problem happens whenever I add something new to my local d.ts that is flagged as an error. Even when I reverse the change, all of my previous definitions are now not picked up, and I will usually spend the rest the of the day getting resolving this. Sometimes re-installing TypeScript helps, sometimes not.